A major root-associated acid phosphatase in Arabidopsis, AtPAP10, is regulated by both local and systemic signals under phosphate starvation.

Abstract

The induction and secretion of acid phosphatases (APases) is a universal response of plants to phosphate (Pi) starvation. AtPAP10 (Arabidopsis purple acid phosphatase 10) is a major Pi starvation-induced APase that is associated with the root surface in Arabidopsis. So far, the roles of local and systemic signalling in regulating root-associated AtPAP10 activity remain largely unknown. In this work, we show that a decrease of local, external Pi availability is sufficient to induce AtPAP10 transcription in roots in the presence of sucrose, a systemic signal from shoots, whereas the magnitude of the induction is affected by the Pi status of the whole plant. Once the AtPAP10 mRNAs are synthesized in roots, subsequent accumulation of AtPAP10 proteins in root cells and increase in AtPAP10 activity on the root surface are mainly controlled by local signalling. Previously, ethylene has been demonstrated to be a positive regulator of AtPAP10 activity. In this study, we provide evidence that under Pi deficiency ethylene mainly modulates enzymatic activity of AtPAP10 on the root surface, but not AtPAP10 transcription and protein accumulation, suggesting that it functions as a local signal. Furthermore, our work indicates that the effect of ethylene on the induction of root-associated AtPAP10 activity depends on sucrose, but that the effect of sucrose does not depend on ethylene. These results reveal new insights into the distinct roles of local and systemic signalling in the regulation of root-associated AtPAP10 activity under Pi starvation.

• Authors: Ye Zhang, Xiaoyue Wang, Shan Lu, Dong Liu
• Journal: Journal of experimental botany (J Exp Bot) Vol. 65 Issue 22 Pg. 6577-88 (Dec 2014) ISSN: 1460-2431 [Electronic] England
• PMID: 25246445 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Chemical References

• Arabidopsis Proteins
• Ethylenes
• Phosphates
• RNA, Messenger
• Sucrose
• ethylene
• PAP10 protein, Arabidopsis
• Acid Phosphatase

Topics

• Acid Phosphatase (genetics, metabolism)
• Arabidopsis (drug effects, enzymology, genetics)
• Arabidopsis Proteins (genetics, metabolism)
• Ethylenes (pharmacology)
• Gene Expression Regulation, Plant (drug effects)
• Genes, Plant
• Models, Biological
• Mutation (genetics)
• Phosphates (deficiency, pharmacology)
• Plant Roots (drug effects, enzymology, genetics)
• RNA, Messenger (genetics, metabolism)
• Signal Transduction (drug effects, genetics)
• Sucrose (pharmacology)
• Transcription, Genetic (drug effects)